1. Field of the Invention
The present invention relates to a cage for lipless roller bearings, and more particularly to a two-row bearing in which rollers are separated by wedge- or cusp-shaped support members in a supporting area of the cage.
2. Description of the Related Art
An example of a cage for lipless roller bearings is seen, for example, in U.S. Pat. No. 2,611,670. In that patent, the rows of rollers of a two-row self-aligning bearing rest against surfaces of an inner separator in the cage that are substantially parallel to each other. It is apparently acceptable for the rollers to rest against a separator having such parallel resting surfaces when their axial components of motion are taken up by a central lip on the inner ring. However, if such a lip is absent, such a separator is unacceptable, since a sufficient lubricating film for the forces which occur cannot build up on the opposite parallel surfaces. There is increased friction and as a result rapid heating of the bearing, which can lead to an early failure of the bearing.
In Federal Republic of Germany Pat. No. 46 55 35, a roller bearing is shown in which a window cage has certain sections which are inclined at a slight angle to the roller end surfaces, rather than being parallel thereto. In that case, however, the bearing is only a single-row bearing. Furthermore, the wedge surfaces do not extend over the entire supporting area of the cage, which moreover is relatively small. For these reasons the problem of insufficient lubrication is not alleviated.